Internal combustion engine structure



Jan. 5, 1937; R, DAUB 2,0661394 INTERNAL COMBUSTION ENGINE STRUCTURE Filed April 21, 1953 2 Sheets-Sheet l Q N INVENTOR Rudolph Daub ATTORNEY Y Jan. 5, 1937. R DAUB 2,066,394

INTERNAL COMBUSTION ENGINE STRUCTURE Filed April 21, 1933 2 Sheets-Sheet 2 0 3 Q5 INVENTJR 35 N 3 Rudolphflaab 0 O BY I d mry I 7 ATTORNEY Patented Jan. 5, 1937 UNITED STATES INTERNAL COIVIBUSTION ENGINE STRUCTURE Rudolph Daub, Paterson, N. J., assignor to Wright Aeronautical Corporation, a corporation of New York Application April 21, 1933, Serial No. 667,142

This invention relates to internal combustion engines and particularly to the type of engines in which the crankcases are of the "barrel type,

i. e., in which circular discs are employed as crankshaft bearings.

In this type of engine wherein cylinders are in line or radially disposed, the outside diameter of the disc must be slightly larger than that of the circular space of rotation required by the crank throws, in order to permit the axial insertion of the crankshaft and discs in assembled relation, into such a barrel type crankcase. The large bore for receiving these discs renders the crankcase extremely weak against high explosion loads as are encountered for instance, in engines operating on the Diesel cycle.

In engines where the bore can be avoided at one end by casting or forging transverse walls integrally with the crankcase as for instance in radial engines, it has been found necessary to provide special means to withstand high explosion loads. One of said special means has been to form the crankcase and walls of steel which is costly and in many applications too heavy. Another means in cast or forged aluminum crankcases where the transverse walls are integrally formed with the crankcase is to subject the walls and crankcase to compression by preloading, which consists of encircling hoops therearound and subjecting the hoops to considerable tension by the use of turn-buckles thereon. This last method is impractical, especially in in-line engines.

Other means for withstanding the explosion loads in engines where transverse discs are separate of the crankcase is, to make these discs slightly smaller in diameter than the bore in the crankcase, so as to be able to bolt the discs to the crankcase thereby to place the discs in greater tension, or the crankcase in greater compression, than the load transmitted thereto by the explosion.

In engines where discs are separate members and not bolted to the crankcase, another shortcoming is that they chafe in their respective crankcase bores, since they are assembled with a slight push fit at best and the explosion loads further tend to distort the crankcase bores out of round.

In engines having discs in the crankcase to support the crankshaft, another shortcoming is to make the crankshaft bore of such large diameter as to include a bearing bore larger than the crankthrow thereby making the discs more like an annular ring which is easily distorted out of round during tension receiving loads of the explosion.

One of the objects is to prevent relative motion between the discs and the bores and thereby prevent chafing.

Another and very important object is to provide means for taking the explosion loads in the discs thereby relieving the crankcase of tensile stresses. Other objects are to-avoid the shortcomings aforementioned.

A further object is to provide means, in an engine subject to extremely high explosion loads, to avoid completely the interposing of any portion of the crankcase, between the cylinder flanges and discs in order to relieve the crankcase entirely of any stresses or chafing.

It is to be understood that this invention is not to be limited to the exemplary objects or to the showing in the drawings since many other advantages will become apparent and many variations in structure can be made without departing from the spirit of the invention as defined in the appended claims.

Referring to the drawings:

Figure 1 is an end view of a radial engine with the crankcase and part of a diaphragm in section.

Figure 2 is a longitudinal section taken substantially on the line 2-2 of Fig. 1.

Figure 3 is a section taken on the line 33 of Fig. 2.

Figure 4 is an end view of an X type two-cycle engine with certain parts removed and other parts shown in section.

Figure 5 is a longitudinal section substantially on the line 5-5-5 of Fig. 4, with certain parts removed and other parts shown in elevation.

Referring to Fig. 1, a crankcase I0 is provided with a bore II that is adapted to receive discs l2. The diameter of the discs l2 as will be seen by comparison with Fig. 2, is larger than the rotational space required by a crankshaft I3.

The discs I! form the bearings for the crankshaft and may be made of one piece when used as end bearings e and of split construction when used as center bearings as at 0. Cylinders I4 are pro-- vided with flanges l5 and are adapted to seat on the crankcase l0. Bolts I6 are adapted to secure the cylinders to the crankcase and are anchored in the discs.

Although the invention is illustrated in connection with a two row radial engine, it is obvious that the invention is applicable to a single row radial engine by the omission of one crankthrow and one of the end discs l2.

The manner of assembly pinches the crankcase between the cylinders and the discs which prevents relative movement between the parts. The crankcase is further relieved of all explosion loads since they are taken by means of the discs, bolts and the cylinders.

It will be seen that the same construction and function may be had in any in-line, V in-line, etc., and the discs may all be split where assembly or any other conditions make it necescompression.

Referring to Fig. 4, which illustrates a modified form of the invention wherein part of the cylinder sleeve, the part of the block surrounding the sleeve and the cylinder head are all under A crankcase 2c is provided with cylinder blocks 2| which surround the upper part of a cylinder sleeve 22. Toward the inner ends of the sleeve 22 there is provided shoe flanges 23 which are adapted to contact the outer periphery of the discs 24. An annular flange 25 is formed around the sleeves and abuts theinner face of the cylinder block.

Heads 26 provide closures for the cylinders. Long bolts 21 are arranged to pass thru the cylinder heads and the cylinder blocks andare also arranged to pass outside of the sleeves and are adapted to anchor in the discs 24.

This permits the crankcase to be free of any distortion resulting from high explosion loads and further permits of a crankcase barrel having no integral webs or walls at the ends or at the center bearing disc which makes a light and simple casting in this regard. A reenforcement' 28 on sleeve 22' is used in lieu of the crankcase web, and said reenforcement is locally arranged to sustain the above mentioned compression loads Having thus described the invention, what is claimed as new and desired to secure by Letters Patent, is:-

1. In an internal combustion engine the combination of a one-piece tubular crankcase, a crankshaft, a crankthrow on the latter, identical and symmetrically disposed circular crankshaft bearing discs on either side of the crankthrow for receiving an explosion load in tension and for equally distributing the entire load to the crankshaft bearing on either side of the crankthrow, one of said discs being disposed at the end of the crankcase, cylinders symmetrically bridging the discs for distributing the explosion load equally to the discs and symmetrical means anchored in the discs and shouldered in the cylinders for securing said cylinders and said discs to the crankcase and for transmitting the explosion load equally and entirely in tension to each of the discs on either side of the crank-throw.

2. An internal combustion engine including the combination comprising a one-piece tubular crankcase, cylinders on the crankcase, crank-= shaft bearing discs in the crankcase at the ends thereof having crankshaft receiving openings therein of relatively small area as compared to the total area of the discs, and means anchored in the discs and shouldered in the cylinders for transmitting explosion loads in the cylinders to said discs, said means being disposed in the plane of the discs.

3. An internal combustion engine including the combination comprising a one-piece tubular crankcase, cylinders on the crankcase, crankshaft bearing discs in the crankcase and at the the combination comprising a one-piece tubular crankcase, cylinders on the crankcase, crankshaft bearing discs in the crankcase including discs at the ends thereof, said discs having openings therein of relatively small area as compared to the total area of the discs, and means anchored in the discs'and shouldered in the cylinders for transmitting explosion loads in the cylinders to said discs, said means being disposed in the plane of the discs, said discs being symmetrically disposed on both sides of the cylinders.

5. In an internal combustion engine, the combination of a tubular crankcase open at the ends thereof, cylinders on the crankcase, crankshaft bearing discs at the ends of the crankcase, and means anchored in the discs and shouldered on the cylinders for securing said discs and cylinders to the crankcase.

6. In an internal combustion engine, the combination including a one-piece tubular crankcase, cylinders on the crankcase, more than two substantially identical crankshaft bearing discs in the crankcase, including a disc at each end of the crankcase, each of said cylinders being disposed between two adjacent discs, and means anchored in the discs and shouldered on the cylinders for securing said discs and cylinders to the crankcase whereby the explosion forces in any cylinder are distributed equally to the discs to which it is secured.

7. In a radial internal combustion engine crankcase structure, the combination including a tubular crankcase having a circular disc receiving bore at the end thereof, cylinders on the crankcase, substantially identical crankshaft bearing discs having crankshaft bores of smaller diameter than the clearance circle of the crankthrow, one of said discs being disposed in the circular bore of the crankcase thereby forming an end wall for the crankcase, another of said discs being disposed in the crankcase and symmetrically opposite to the first mentioned disc with respect to the centerv of the cylinder, and substantially identical means anchored in the discs, passing through the crankcase and shouldered on the cylinders, for securing said discs and cylinders to the crankcase whereby the explosion forces acting between the cylinders and the crankshaft are equally received in the discs.

8. In an internal combustion engine having a tubular crankcase with open ends, a crankshaft within the crankcase, cylinders on the crankcase,

means for attaching the cylinders against explo-- ders whereby the explosion forces in the cylinders are received substantially equally on both sides of the cylinders.

9. In an internal combustion engine having a tubular crankcase with open ends, cylinders on the crankcase, a crankshaft within the crankcase, two crankshaft bearing discs in the ,crankcase substantially at the ends thereof and'substantially' equally disposed on each side of the crankthrow of the crankshaft, means for trans mitting the explosion forces in the cylinders to the discs comprising bolts anchored in the discs and shouldered on the cylinders whereby said explosion forces are received substantially equally on both sides of the cylinders.

' RUDOLPH DAUB. 

